Process for forming a divided conduit

ABSTRACT

A method of producing a divided conduit comprising forming a strip-shaped substrate having a first longitudinal edge and a second longitudinal edge. The strip-shaped substrate is a strip-shaped textile or a strip-shaped film. Then extruding a molten thermoplastic into the form of a conduit and placing the one strip-shaped substrate within the extruded conduit during or directly after conduit formation. The first longitudinal edge and the second longitudinal edge of the strip-shaped substrate adhere to or embed into the inner surface of the conduit.

RELATED APPLICATIONS

This application is related to U.S. patent application Ser. No.13/088,837, “Divided Conduit” filed on Apr. 18, 2011, now U.S. Pat. No.8,809,682.

TECHNICAL FIELD

The present disclosure generally relates to processes to form dividedconduits into which cables, such as fiber optic cables, coaxial cables,and the like, may be positioned. More particularly, the presentdisclosure relates to processes to form divided conduits having astrip-shaped substrate attached to the conduit on its longitudinal edgesseparating the conduit into two or more longitudinal channels.

BACKGROUND

Cable, such as fiber optic communication cable, is often providedunderground in great lengths, and may even extend for many miles. It isknown in the art to bury the cable in the ground so that the areaabove-ground is not cluttered with the cable and its respective supportapparatus. Furthermore, by positioning the cable underground, it is moreprotected from the weather and other potentially damaging circumstances.

It is also known in the cable art to position the cable within a conduitin order to more fully protect the cable during in-ground installations.The conduit, which is often formed from lengths of polyvinyl chloridetubing, polyethylene tubing or the like, is laid in the ground, afterwhich a rope is placed in the conduit either by blowing or rodding. Therope, in turn, is attached to one of the communication cables. Bypulling the rope from one end of the conduit, the cable is drawn throughthe conduit into position. Once placed within the conduit, the cable isprotected from damage which may be caused by weather, water, and thelike.

When a conduit is in place, it may be subsequently desired to run asecond communications cable at the same location. As such, it would bedesirable from a cost and time standpoint to make use of the dead spacewithin an existing conduit, rather than lay a new length of conduit.However, it has been found that it is difficult to merely insert asecond cable into a conduit that already contains a first cable. When arope is blown or “snaked” into a conduit already containing a cable (orwhen a second cable is “snaked” through a conduit with a pre-laidcable), the rope (or cable) is often impeded by the first cable. In suchcases, the rope (or second cable) becomes tangled with, or twistedaround, the first cable, causing damage to the cables.

It has been suggested to provide a divider to be inserted into a conduitin order to separate the conduit into discrete sections, thus makinginsertion of the second cable easier. A problem has been encountered inthat when conduit is placed over long distances, undulations willinvariably occur therein. Also, planned curves, such as at underpassesor the like, will often be encountered rendering the placement of knowndividers therein difficult, if not impossible.

A need exists, therefore, for a device to separate or partition aconduit, such as an underground communication cable conduit, intodiscrete sections. A need also exists for a partitioning device whichwill provide for improved use of the space within a conduit.

BRIEF SUMMARY

Provided is a method of producing a divided conduit comprising forming astrip-shaped substrate having a first longitudinal edge and a secondlongitudinal edge. The strip-shaped substrate is a strip-shaped textileor a strip-shaped film. Then extruding a molten thermoplastic into theform of a conduit and placing the one strip-shaped substrate within theextruded conduit during or directly after conduit formation. The firstlongitudinal edge and the second longitudinal edge of the strip-shapedsubstrate adhere to or embed into the inner surface of the conduit. Alsodisclosed is a process to form the divided conduit by co-extruding thestrip-shaped film and the conduit simultaneously.

BRIEF DESCRIPTION OF THE DRAWINGS

An exemplary embodiment of the present invention will now be describedby way of example, with reference to the accompanying drawings, wherein:

FIG. 1 is an illustration of one embodiment of the invention having onestrip-shaped substrate forming two channels.

FIG. 2 is an illustration of one embodiment of the invention having twostrip-shaped substrates forming three channels.

FIG. 3 is an illustration of one embodiment of the invention having onestrip-shaped substrate forming three channels.

FIG. 4 is an illustration of one embodiment of the invention having onestrip-shaped substrate forming two channels, where the strip-shapedsubstrate is moved towards the inner surface of the conduit.

FIG. 5 is an illustration of one embodiment of the invention having twostrip-shaped substrates forming five channels.

DETAILED DESCRIPTION

The divided conduits described herein are readily manufactured. Eachdivided conduit provides a structure that allows cables to be pulledthrough without snagging or excessive heat build-up due to friction. Inaddition, the divided conduits do not allow contact or alternationlosses between adjacent cables in other channels of the conduit.

The term “strip-shaped substrate” refers to a long strip of flexiblematerial made of any suitable material such a textile or film. The term“longitudinal edges” refers to the edges along the length of thestrip-shaped substrate. The term “longitudinal axis” refers to the axisof the strip-shaped substrate along its length. “Integral”, in thisapplication, means that two of more materials are connected with eachother without the further use of any glues or adhesives. The dividedconduit may be considered to be integral.

Referring now to FIG. 1, there is shown one embodiment of the dividedconduit 10. In FIG. 1, the conduit 100 contains one strip-shapedsubstrate 200. The strip-shaped substrate 200 has two longitudinaledges, a first longitudinal edge 200 a and a second longitudinal edge200 b, both of which are adhered to the inner surface 100 a of theconduit 100. This forms two channels 310 and 320 where cables or otherelongated structures may be placed. The cables or other elongatedstructures may be placed into the channels during the formation of thedivided conduit, after the conduit is formed, or after the conduit isinstalled. The divided conduit formed is flexible and a lower weightthen some alternative technologies.

The conduit 10 (also sometimes referred to as a pipe or tube), may beany suitable conduit formed from an extrudable material such as athermoplastic. The conduit may have any suitable wall thickness, innerdiameter, and outer diameter. Conduits for use in the fiber optic fieldtend to have an inner diameter of about 12 mm to 50 mm. In otherembodiments, the conduit may have a very large inner diameter, forexample from about 100 mm to 150 mm, or may have a very small diametersuch as less than about 50 mm. The conduit is preferably flexible. Inone embodiment, the conduit is formed from a polymer selected form thegroup consisting of polyethylene, polypropylene, polyester, andpolyvinyl chloride. The conduit may contain a bumpy finish to reduce theamount of contact the film has with the cable, pull line, or otherelongated structure. In one embodiment, the inner or outer surface ofthe conduit has a textured surface. One example of a textured surface isan “orange peel” finish, where the texture resembles the bumpy surfaceof the skin of an orange (fruit). This textured surface may serve toreduce the coefficient of friction and allow for easier insertion ofcables or other elongated structures. The conduit may be smooth-wall,corrugated, or the like.

The strip-shaped substrate 200 may be formed of any suitable material.The strip-shaped substrate should be flexible, have a low coefficient offriction to avoid cable damage and preferably have a high strength toavoid tearing during cable installation. In one embodiment, thestrip-shaped substrate should be able to withstand the extrusiontemperatures of the thermoplastic polymer used to form the conduit.

Preferably, the coefficient of friction for the strip-shaped substrate(dynamic or sliding coefficients of friction) are between about 0.06 toabout 0.14, and a narrower range of about 0.08 to about 0.13, may alsobe used. In one embodiment, the breaking tensile strength of the presentfabric is in the range of from about 45 kg/cm to about 70 kg/cm. Inanother embodiment, the elongation percentages of the strip-shapedsubstrate are between 2% and 5% at 22.5 kg of force and between 5% and10% at 45.5. Kg of force. The strip-shaped substrate preferably has athickness of about 0.025 inches to 0.100 inches. The strip-shapedsubstrate preferably has a breaking strength of about 200 lbs/cm to 600lbs/cm. The strip-shaped substrate preferably has air permeability of 10cm³/cm²/s to 70 cm³/cm²/s. Preferably the strip-shaped substrate has arigidity of between about 100 and 400 grams force as measured by ASTMD6827.

In one embodiment, the strip-shaped substrate 200 is a strip-shapedtextile. The strip-shaped textile used may be any suitable textile, butis preferably one that is flexible, has a low coefficient of friction,and a high tensile strength. The textile may be a knit, woven,non-woven, or unidirectional. The strip-shaped textile may haveadditional function chemistries such as low friction, fire resistance,adhesion, or color added. The chemistries may be added to the yarnsduring yarn formation or applied onto the yarns before or after textileformation. In one embodiment, the textile has a weight of about 2 to 20ounces per yard and in another embodiment has a weight of about 10 to 12ounces per yard. The space between the yarns within the textile will aidin breathability of the textile and the flexibility of the dividedconduit. Further, having these shapes should allow for easier movementof the strip-shaped textile within the divided conduit to change thesize of the channels and make it easier to install cables in betweenempty channels.

In one embodiment, the strip-shaped textile is a woven textile. Thefabric base may also be, for example, plain, satin, twill, basket-weave,poplin, jacquard, and crepe weave textiles. Preferably, the woventextile is a plain weave textile. It has been shown that a plain weavehas good abrasion and wear characteristics. A twill weave has been shownto have good properties for compound curves so may also be preferred forsome strip-shaped textiles. The end count in the warp direction isbetween 35 and 70 in one embodiment. The denier of the warp yarns isbetween 350 and 1200 denier in one embodiment. In one embodiment, thetextile is air permeable which increases the flexibility of the dividedconduit and may allow for easier movement of the strip-shaped textilewithin the divided conduit to change the size of the channels and makeit easier to install cables in between empty channels.

In another embodiment, the strip-shaped textile is a knit, for example acircular knit, reverse plaited circular knit, double knit, single jerseyknit, two-end fleece knit, three-end fleece knit, terry knit or doubleloop knit, weft inserted warp knit, warp knit, and warp knit with orwithout a micro-denier face.

In another embodiment, the strip-shaped textile is a multi-axial, suchas a tri-axial fabric (knit, woven, or non-woven). In anotherembodiment, the strip-shaped textile is a bias fabric. In anotherembodiment, the strip-shaped textile is a non-woven. The term non-wovenrefers to structures incorporating a mass of yarns that are entangledand/or heat fused so as to provide a coordinated structure with a degreeof internal coherency. Non-woven fabrics for use as the strip-shapedtextile may be formed from many processes such as for example, meltspunprocesses, hydroentangeling processes, mechanically entangled processes,stitch-bonded and the like. In another embodiment, the strip-shapedtextile is a unidirectional textile and may have overlapping yarns ormay have gaps between the yarns.

The yarns making up the strip-shaped textile forming the strip-shapedsubstrate 200 may be any suitable yarn. “Yarn”, in this application, asused herein includes a monofilament elongated body, a multifilamentelongated body, ribbon, strip, fiber, tape, and the like. The term yarnincludes a plurality of any one or combination of the above. The yarnsmay be of any suitable form such as spun staple yarn, monofilament, ormultifilament, single component, bi-component, or multi-component, andhave any suitable cross-section shape such as circular, multi-lobal,square or rectangular (tape), and oval.

Some suitable materials for the yarns include polyamide, aramid(including meta and para forms), rayon, PVA (polyvinyl alcohol),polyester, polyolefin, polyvinyl, nylon (including nylon 6, nylon 6,6,and nylon 4,6), polyethylene naphthalate (PEN), cotton, steel, carbon,fiberglass, steel, polyacrylic, polytrimethylene terephthalate (PTT),polycyclohexane dimethylene terephthalate (PCT), polybutyleneterephthalate (PBT), PET modified with polyethylene glycol (PEG),polylactic acid (PLA), polytrimethylene terephthalate, nylons (includingnylon 6 and nylon 6,6); regenerated cellulosics (such as rayon orTencel); elastomeric materials such as spandex; high-performance fiberssuch as the polyaramids, and polyimides natural fibers such as cotton,linen, ramie, and hemp, proteinaceous materials such as silk, wool, andother animal hairs such as angora, alpaca, and vicuna, fiber reinforcedpolymers, thermosetting polymers, blends thereof, and mixtures thereof.

In one embodiment, the yarns of the textile have a greater meltingtemperature than the thermoplastic polymer forming the conduit so theywill not melt during the extrusion process forming the divided conduit.In another embodiment, the yarns do not have a melting temperature (suchas yarns from a thermoset polymer or some natural fibers), but must beable to withstand the extrusion conditions of the conduit withoutsignificant loss in physical properties.

In one embodiment, the textile contains warp yarns and weft yarns whichare monofilament. In another embodiment, the warp yarns are monofilamentand the weft yarns are multi-filament. In another embodiment, the warpyarns are monofilament and the weft yarns are an alternating arrangementof monofilament and multifilament yarns. In another embodiment, the warpyarns and weft yarns are multi-filament. In another embodiment, the warpyarns are multi-filament. In another embodiment, the warp yarns aremultifilament and the filling yarns are monofilament. The phrase“alternating arrangement” refers to a repeating pattern of monofilamentto multifilament yarns. In one embodiment, the arrangement ofmonofilament to multifilament yarns is 1:1. Other ratios, such as 1:2,1:3, 2:3, 3:4, or 3:5, for example, may also be employed, as productspecifications dictate. For the embodiments containing monofilamentyarns, the denier of the yarns is preferably between about 200 and 800denier. For the embodiments containing multifilament yarns, the denierof the yarns is preferably between about 200 and 1,000 denier.

The strip-shaped substrate 200 may also be a strip-shaped film.Preferably, this film is made of a thermoplastic polymer, but may alsobe made of any other suitable material including a thermoset. Somesuitable thermoplastic polymers include, but are not limited topolypropylene, polyethylene, polyester, polyvinyl alcohol, blendsthereof, and co-polymers thereof. Preferably, the film is formed from athermoplastic selected from the group consisting of polyester,polyolefin, and polyamide. The strip-shaped film may have perforationsor be continuous. Perforations will aid in breathability of the film andthe flexibility of the divided conduit. Further, having perforationsshould allow for easier movement of the strip-shaped film within thedivided conduit to change the size of the channels and make it easier toinstall cables in between empty channels. Further, the strip-shaped filmmay be fiber reinforced or not. A film containing fibers may increasethe breaking strength of the film. In one embodiment, at least one ofthe surfaces of the strip-shaped film has a textured surface. Oneexample of a textured surface is an “orange peel” finish. This texturedsurface may serve to reduce the coefficient of friction and allow foreasier insertion of cables or other elongated structures.

In some embodiments, an already formed, free-standing strip-shaped filmis inserted into the conduit during (or directly after) the extrusion ofthe pipe. In one embodiment, this strip-shaped film is oriented, meaningthat after extrusion the film is further stretched in at least one axis.This orienting serves to increase the dimensional stability and strengthof the film to be placed into the conduit. In one embodiment, thepolymer that the film is made of has a higher melting temperature thanthe polymer used to form the conduit. In another embodiment, the filmdoes not have a melting temperature (such as thermoset polymer). In thisembodiment, the film must be able to withstand the extrusion conditionsof the conduit without significant loss in physical properties. Duringthe manufacturing processes, the already formed, freestandingstrip-shaped film is introduced into the conduit during or directlyafter extrusion of the conduit and the film must not lose significantphysical properties during this process. The strip-shaped film may havechemistries added to the polymer before film formation or applied ontothe formed film to provide for low friction, fire resistance, adhesion,or color. The film may contain a bumpy finish to reduce the amount ofcontact the film has with the cable, pull line, or other elongatedstructure.

While in FIG. 1 there is shown the strip-shaped substrate 200 adhered tothe inner wall of the conduit 100 on both the first longitudinal edge200 a and the second longitudinal edge 200 b, there may be embodimentswhere only one edge of the strip-shaped substrate is adhered to theinner wall of the conduit 100.

In one embodiment, the longitudinal edge(s) (200 a, 200 b) of thestrip-shaped substrate 200 are embedded into the inner surface of theconduit. Being “embedded” means that the edges of the strip-shapedsubstrate are not just adhered to the surface of the inner wall byactually reside within the wall of the conduit such that the edge iscompletely covered, surrounded, and entrenched by the material of theconduit.

In one embodiment, the width of the strip-shaped substrate, defined asthe distance between the first longitudinal edge 200 a and the secondlongitudinal edge 200 b is between about 32 and 60% of the innercircumference of the conduit. In another embodiment, the width of thestrip-shaped substrate 200 is greater than the diameter of the conduit.For example, in FIG. 4, there is shown another embodiment of the dividedconduit a longer width of the strip-shaped substrate (or film) isbeneficial as it may move towards the inner surface of the conduit intoone of the chambers of the divided conduit thus opening the other(unfilled) channel for less friction and easier cable installation.

FIG. 2 illustrates an additional embodiment of the invention where thedivided conduit 10 contains a conduit 100 with two strip-shapedsubstrates 200, each strip-shaped substrates 200 having a firstlongitudinal edge 200 a and a second longitudinal edge 200 b adhered tothe inner wall of the conduit 100. This forms three channels 310, 320,330 for the placement of cables or elongated structures 400. While FIG.2 is shown with two strip-shaped substrates 200, there may beembodiments having three or more strip-shaped substrates 200.

FIG. 3 illustrates an additional embodiment of the invention where thedivided conduit 10 contains a conduit 100 with one strip-shapedsubstrates 200, having a first longitudinal edge 200 a and a secondlongitudinal edge 200 b adhered to the inner wall of the conduit 100 aswell as an additional point 200 c of the material (between the firstedge 200 a and the second edge 200 b) optionally adhered to the innerwall of the conduit 100. The additional point 200 c runs along thelongitudinal axis of the fabric. The conduit 100 having one strip-shapedsubstrate 200 forms a divided conduit having three channels 310, 320,330.

FIG. 5 is an illustration of one embodiment of the invention having twostrip-shaped substrates forming five channels. Each of the twostrip-shaped substrates 200, having a first longitudinal edge 200 a anda second longitudinal edge 200 b are adhered to the inner wall of theconduit 100. The conduit 100 having two strip-shaped substrates 200forms a divided conduit having five channels 310, 320, 330, 340, 350.

One process for forming the divided conduit begins with an alreadyformed, free-standing, strip-shaped substrate 200. This already formedstrip-shaped substrate is then introduced to the conduit extrusionprocess where the first and second edges 200 a, 200 b of thestrip-shaped substrate 200 are adhered to or embedded into the innersurface of the conduit 100 during the extrusion of the conduit ordirectly after the extrusion (while the polymer of the conduit is stillabove its T_(g)). In this embodiment, the materials of strip-shapedsubstrate (yarns for a textile or polymer for a film) preferably have ahigher melting temperature than the polymer forming the conduit. In thecase where the materials of the strip-shaped substrate 200 do not have amelting temperature, preferably strip-shaped substrate must be able towithstand the conduit forming (extrusion processing) conditions withouta significant loss in physical properties. During the extrusion processwhere the conduit is formed, the strip-shaped substrate is introducedinto the forming conduit while the conduit is still at least partiallymolten and pressed into the surface of the molten conduit with, forexample, a roller or a flexible rib. This allows the edges of thestrip-shaped substrate to be adhered or embedded into the material ofthe conduit. Multiple strip-shaped substrates can be introduced into theforming conduit resulting in multiple channels such as shown in FIGS. 2and 5.

In one embodiment, there are two strip-shaped substrates introducedduring the extrusion process to form a conduit having 3 channels 310,320, and 330 such as shown in FIG. 2. In another embodiment, thestrip-shaped substrate 200 is inserted into the extrusion process suchthat the two edges (first longitudinal edge 200 a and secondlongitudinal edge 200 b) are adhered to the inner wall of the conduit aswell as another section of the strip-shaped substrate along itslongitudinal axis. In this embodiment, shown in FIG. 3, the firstlongitudinal edge 200 a, second longitudinal edge 200 b, and anadditional point 200 c are adhered or embedded into the polymer of theconduit 100. With the one strip-shaped substrate 200, 3 channels 310,320, and 330 are created.

In another embodiment, the conduit is formed from simultaneouslyextruding a first molten thermoplastic and a second moltenthermoplastic. This simultaneous extrusion of the first and secondpolymer may be from co-extrusion. The first and second thermoplasticsare distinct and different polymers having different compositions,melting temperatures, and/or physical characteristics. The firstthermoplastic forms the conduit and the second thermoplastic forms thestrip-shaped film within the conduit. The first thermoplastic isselected from the group consisting of polyethylene, polypropylene,polyester, and polyvinyl chloride. The second thermoplastic is selectedfrom the group consisting of polyester, polyolefin, and polyamide. Inone embodiment, the second thermoplastic has a melting temperaturegreater than the melting temperature of the first thermoplastic. Inanother embodiment, the second thermoplastic polymer is the same polymeras the first thermoplastic, just thinner to allow bending of thestrip-shaped film. In another embodiment, the strip-shaped film couldhave perforations to allow air to flow between channels allowing thestrip-shaped film to move out of the way (towards the inner surface ofthe conduit) when a rope or cable is pulled though the conduit thusincreasing the conduit cross-section which results in less friction andeasier pull.

In this embodiment, the second molten thermoplastic forms a onestrip-shaped substrate in the form of a strip-shaped film having a firstlongitudinal edge and a second longitudinal edge embedded into the firstthermoplastic of the conduit forming two channels. In anotherembodiment, the second molten thermoplastic forms 2 strip-shapedsubstrates forming 3 channels. In another embodiment, the second moltenthermoplastic forms at least 3 strip-shaped substrates, each having atleast one of the edges embedded into the first thermoplastic of theconduit.

The divided conduit may optionally contain pull lines or cords. Thesemay be placed inside the conduit in at least one channel duringmanufacture of the divided conduit, after conduit formation, or afterconduit placement. Pull lines, which are typically tightly woven,relatively flat strips of material, may be used for pulling cablesthrough the channels. However, pull cords having a substantially roundcross-section may be used successfully with smaller diameter cables.

In one embodiment, the pull lines are formed of tightly woven, polyestermaterial, which exhibits a tensile strength of between about 400 poundsand about 3,000 pounds. In an alternate embodiment, a twisted round rope(for example, a multi-ply cord) may be used, where such pull cords aremade of polypropylene, polyester, and the like.

The divided conduit is designed to contain cables or other elongatedobjects. These may be placed inside the conduit in at least one channelduring manufacture of the divided conduit, after conduit formation, orafter conduit placement.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the inventionand does not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention.Variations of those preferred embodiments may become apparent to thoseof ordinary skill in the art upon reading the foregoing description. Theinventors expect skilled artisans to employ such variations asappropriate, and the inventors intend for the invention to be practicedotherwise than as specifically described herein. Accordingly, thisinvention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

What is claimed is:
 1. A method of producing a divided conduitcomprising, in order: forming a strip-shaped textile having a firstlongitudinal edge and a second longitudinal edge, wherein thestrip-shaped textile is selected from the group consisting of a woven,non-woven, and knit, wherein the strip-shaped textile is air permeable;extruding a molten thermoplastic polymer into the form of an at leastpartially molten conduit having an inner surface and an outer surface,wherein the inner surface and outer surface of the conduit iscontinuous; placing at least one strip-shaped substrate within the atleast partially molten conduit during or directly after conduitformation; pressing the first longitudinal and second longitudinal edgesof the strip-shaped substrate into the inner surface of the at leastpartially molten conduit, wherein the first longitudinal and secondlongitudinal edges of the strip-shaped substrate embed into the innersurface of the conduit.
 2. The method of claim 1, wherein the distancebetween the first longitudinal and second longitudinal edge of thestrip-shaped textile is between about 32 and 60% of the circumference ofthe inner surface of the conduit.
 3. The method of claim 1, wherein thedistance between the first longitudinal and second longitudinal edge ofthe strip-shaped textile is greater than the inside diameter of theconduit.
 4. The method of claim 1, wherein at least two strip-shapedtextiles are placed within the conduit during or directly afterformation.
 5. The method of claim 1, wherein the strip-shaped textilecomprises a polymer having a melting temperature greater than themelting temperature of the thermoplastic polymer of the conduit.
 6. Themethod of claim 1, wherein the strip-shaped textile forms at least twoflexible, longitudinal channels for enveloping cables.